Solar energy could meet one-sixth of global demand for heating and cooling in under 40 years

Investing in a broad range of solar heating and cooling technologies could save 800 megatonnes of CO2 emissions per year by 2050, IEA report finds

9 July 2012

Solar energy could account for around one-sixth of the world’s total low-temperature heating and cooling needs by 2050, according to a roadmap launched today by the International Energy Agency (IEA). This would eliminate some 800 megatonnes of carbon dioxide (CO2) emissions per year, or more than Germany’s total CO2 emissions in 2009.

The IEA’s Solar Heating and Cooling Roadmap outlines how best to advance the global uptake of solar heating and cooling (SHC) technologies, which produce very low levels of greenhouse-gas emissions. Some SHC technologies, such as domestic hot water heaters, are already widely in use in certain countries, but others are just entering the development phase.

While solar heating and cooling today makes a modest contribution to world energy demand, the roadmap envisages that if governments and industry took concerted action, solar energy could annually produce more than 16% of total final energy use for low-temperature heat and nearly 17% for cooling. This would correspond to a 25-fold increase in absolute terms of SHC technology deployment in the next four decades.

“Given that global energy demand for heat represents almost half of the world’s final energy use – more than the combined global demand for electricity and transport – solar heat can make a significant contribution in both tackling climate change and strengthening energy security,” said Paolo Frankl, Head of the IEA’s Renewable Energy Division.

Benefiting warm climate countries

In addition to replacing fossil fuels that are directly burned to produce heat, solar heating technologies can also replace electricity used for heating water as well as individual rooms and buildings.

This would be especially welcome in warm climate countries without gas infrastructure and lacking alternative heating fuels. South Africa is cited as an example of a country that would benefit, as electric water heating currently accounts for a third of average household (coal-based) power consumption there.

On top of this, the report notes that solar thermal cooling technology – in which the sun’s heat can be used to cool air – can reduce the burden on electric grids at times of peak cooling demand by fully or partially replacing conventional electrically powered air conditioners in buildings.

Use in industry

The roadmap also stresses the scope for expanding use of these technologies in industry. Often overlooked is several industry sectors’ significant energy demand for low- and medium-temperature heat in such processes as washing, drying agricultural products, pasteurisation and cooking.

Those industrial processes offer enormous potential for solar heating technologies, which could supply up to 20% of total global industrial demand for low temperature heat by 2050. However, dedicated policy support is needed for these technologies to be used effectively.

Key actions

To realise the goal outlined, the IEA roadmap recommends key actions which governments should take over the next decade. These include creating a stable, long-term policy framework for solar heating and cooling; introducing economic incentives; and addressing barriers such as a lack of quality-control standards.

Other recommendations are for governments to provide funding and support-mechanisms for research, development and demonstration so promising technologies that are at an early stage can reach high-volume commercial production within 10 years. The roadmap also states that aid organisations in developing countries should expand efforts to accelerate the deployment of mature and competitive SHC technologies.